ArmPkg/ArmLib: clean up library includes

ArmPkg/ArmLib: clean up library includes

Suspiciously, ArmLib's INF does not contain a [LibraryClasses]
section at all, but it turns out that all the library includes
it contains (except for ArmLib.h itself) are actually bogus so
let's just drop all of them. While at it, replace <Uefi.h> with
the more accurate <Base.h> for a BASE type module, and put the
includes in a consistent order.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>